Talk given October 1, 2007 for the UC-Berkeley Ear Club.
Richard F. Lyon Google Mountain View, CA
"Cochlea Modeling Retrospective"
There is a long history of cochlea modeling that people need to be aware of, to help design, optimize, and evaluate neuromorphic hearing systems. In particular, it's important to understand: the notions of time-frequency and time-scale separation and the classes of filters that these notions imply; the large-scale AGC and "essential" nonlinearities that compress the wide dynamic range of sound into a small representation range; the indirect relationship of transfer functions to tuning curves; the relative properties of cascade and parallel filterbanks; the need for higher-order poles to get realistic transfer functions; why zeros are needed to keep the delay realistic; and why and how to capture temporal structure for subsequent processing. We review these topics and some early contributions to this field.